阅读说明：本技术 一种海上风电导管架基础用直缝埋弧焊钢管制备工艺 (Preparation process of longitudinal submerged arc welded steel pipe for offshore wind power jacket foundation ) 是由 贾庆浩 吴宏根 王云飞 金琴 于 2020-12-23 设计创作，主要内容包括：本发明属于钢管制造技术领域,具体涉及一种海上风电导管架基础用直缝埋弧焊钢管制备工艺,包括以下步骤,对钢板的两边缘进行双面铣削,达到预设的钢板宽度,然后采用预弯机对钢板两端进行预弯,在钢板的卷制方向留有预弯直边；预弯后的板边经多道轧辊滚压,形成单管管坯,将单管管坯进行纵缝焊接制得单管管节；对单管管节的管端进行平头加工处理；对平头加工处理后的单管管节组对并环缝焊接制得管段；本发明有效清除了焊接处的粉尘、油污、水分等影响焊缝质量的因素,不仅防止已清理过的焊接处被再次污染影响焊缝质量,还能促使焊缝中氢的逸出,有效避免了气孔和裂纹的产生,从而改善了焊缝的耐超低温冲击性能。(The invention belongs to the technical field of steel pipe manufacturing, and particularly relates to a process for preparing a longitudinal submerged arc welded steel pipe for an offshore wind power jacket foundation, which comprises the following steps of milling two sides of two edges of a steel plate to reach a preset steel plate width, pre-bending two ends of the steel plate by using a pre-bending machine, and reserving pre-bending straight edges in the rolling direction of the steel plate; rolling the pre-bent plate edges by a plurality of rollers to form a single-tube blank, and performing longitudinal seam welding on the single-tube blank to obtain a single-tube joint; performing flat-end processing on the pipe end of the single pipe joint; assembling the single pipe sections subjected to the flat-head processing treatment, and performing girth welding to obtain pipe sections; the invention effectively eliminates the factors of dust, oil stain, moisture and the like at the welding position which influence the quality of the welding seam, not only prevents the cleaned welding position from being polluted again to influence the quality of the welding seam, but also promotes the escape of hydrogen in the welding seam, effectively avoids the generation of air holes and cracks, and thereby improves the ultralow temperature impact resistance of the welding seam.)

1. A preparation process of a longitudinal submerged arc welded steel pipe for an offshore wind power jacket foundation is characterized by comprising the following steps of carrying out double-sided milling on two edges of a steel plate to reach a preset steel plate width, then carrying out pre-bending on two ends of the steel plate by adopting a pre-bending machine, and reserving pre-bending straight edges in the rolling direction of the steel plate; rolling the pre-bent plate edges by a plurality of rollers to form a single-tube blank, and performing longitudinal seam welding on the single-tube blank to obtain a single-tube joint; performing flat-end processing on the pipe end of the single pipe joint; and (4) assembling the single pipe sections subjected to the flat head processing treatment, and performing girth welding to obtain the pipe sections.

2. The process for preparing the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation according to claim 1, wherein a welding groove is formed in a welding node, when the wall thickness T1 of a single pipe joint is 30-85mm, the formed annular welding groove is an X-shaped groove, the truncated edge of the X-shaped groove is 0-3mm, and the upper bevel angle and the lower bevel angle are both 48-52 degrees; when the wall thickness T1 of the single-tube joint is 30-50mm, the provided longitudinal seam welding groove is a V-shaped groove, the truncated edge of the V-shaped groove is 3-6mm, and the angle of the groove is 48-52 degrees; and when the wall thickness T1 of the single pipe joint is 50-85mm, the longitudinal seam welding groove is consistent with the annular welding groove.

3. The process for preparing the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation according to claim 1, characterized in that a welding joint is pre-cleaned before welding, the steel pipe is pre-heated before welding and then heat-preserved after welding after the pre-cleaning, the steel pipe is pre-heated to 180-250 ℃ before welding, the steel pipe is heated to 150-200 ℃ after welding and the heat is preserved for 1-2 hours.

4. The process for preparing the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation according to claim 1, wherein inner welding is performed first and then outer welding is performed, carbon dioxide gas shielded welding is used for backing welding for the inner welding and the outer welding, and longitudinal submerged arc welding filling welding and longitudinal submerged arc welding cover surface welding are used for the inner welding and the outer welding.

5. The process for preparing the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation according to claim 1, wherein the welding wire adopted in the welding process is one of H10Mn2, H08C and H08 CG.

Technical Field

The invention belongs to the technical field of steel pipe manufacturing, and particularly relates to a preparation process of a longitudinal submerged arc welded steel pipe for an offshore wind power jacket foundation.

Background

In recent years, as socio-economy develops rapidly, new energy is obtained for reducing pollution, the national support is provided greatly, and research and development on offshore wind power are accelerated in the market. In offshore wind power facilities, the wind turbine foundation is an important part of offshore wind power development. The jacket form is a common fan foundation, and has the advantages of high overall rigidity and small effect of environmental loads such as waves, water flows and the like, but the process for preparing the longitudinal submerged arc welded steel pipe for the jacket foundation is more complex compared with other foundations.

The pre-bending is one of the main processes of the straight seam submerged arc steel pipe production line, and aims to finish the pre-bending deformation of two sides of a steel plate, if the pre-bending is not carried out, the pipe barrel after the straight seam submerged arc steel pipe is rolled and formed is in a sharp-nose peach shape, which brings trouble to the subsequent pre-welding joint closing and easily causes misalignment or welding burn-through, so that the prepared straight seam submerged arc steel pipe does not meet the quality requirement; in addition, a plurality of difficulties exist during welding, for example, the strength of a welding seam and a base material is ensured, and air holes and cracks are avoided, so that the research on the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation is more and more necessary.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a process for preparing a longitudinal submerged arc welded steel pipe for an offshore wind power jacket foundation.

In order to achieve the purpose, the invention adopts the following technical scheme: a preparation process of a longitudinal submerged arc welded steel pipe for an offshore wind power jacket foundation comprises the following steps of carrying out double-side milling on two edges of a steel plate to reach a preset steel plate width, then carrying out pre-bending on two ends of the steel plate by adopting a pre-bending machine, and reserving pre-bending straight edges in the rolling direction of the steel plate; rolling the pre-bent plate edges by a plurality of rollers to form a single-tube blank, and performing longitudinal seam welding on the single-tube blank to obtain a single-tube joint; performing flat-end processing on the pipe end of the single pipe joint; and (4) assembling the single pipe sections subjected to the flat head processing treatment, and performing girth welding to obtain the pipe sections.

Under the optimal condition, a welding groove is arranged on a welding node, when the wall thickness T1 of a single pipe joint is 30-85mm, the arranged circular seam welding groove is an X-shaped groove, the truncated edge of the X-shaped groove is 0-3mm, and the angle of an upward slope and the angle of a downward slope are both 48-52 degrees; when the wall thickness T1 of the single-tube joint is 30-50mm, the provided longitudinal seam welding groove is a V-shaped groove, the truncated edge of the V-shaped groove is 3-6mm, and the angle of the groove is 48-52 degrees; and when the wall thickness T1 of the single pipe joint is 50-85mm, the provided longitudinal seam welding groove is consistent with the circular seam welding groove.

Under the optimized condition, the welding joint is pre-cleaned before welding, the steel pipe is pre-heated before welding and then heat-insulated after welding after pre-cleaning, the steel pipe is pre-heated to 180-250 ℃ before welding, the steel pipe is heated to 150-200 ℃ after welding, and the heat is insulated for 1-2 hours.

Under the optimal condition, internal welding is carried out first and then external welding is carried out, carbon dioxide gas shielded welding backing welding is adopted for both internal welding and external welding, and longitudinal submerged arc welding filling welding and longitudinal submerged arc welding cover surface welding are adopted.

Preferably, the welding wire used in the welding process is one of H10Mn2, H08C and H08 CG.

Under the preferable condition, the pre-cleaning treatment is to immerse the welding part in the treating agent for 10-20min, take out, wash with clear water and air-dry.

Under the preferable condition, the treating agent comprises the following raw material components in parts by weight: 15-25 parts of pyroglutamic acid cetyl alcohol esterified substance, 1-5 parts of carboxymethyl-beta-cyclodextrin, 1-5 parts of PEG-60 hydrogenated castor oil, 0.5-2 parts of polyaspartic acid, 0.5-2 parts of polydextrose and 300 parts of water-doped material;

the pyroglutamic acid-cetyl alcohol esterified substance is prepared by carrying out esterification reaction on pyroglutamic acid and cetyl alcohol, wherein the molar ratio of the pyroglutamic acid to the cetyl alcohol is 1:1-1.1, the specific preparation method comprises the steps of mixing the pyroglutamic acid and the cetyl alcohol, adding absolute ethyl alcohol to dissolve the mixture to prepare a supersaturated solution, dripping concentrated sulfuric acid to adjust the pH value of the solution to acidity, heating the solution to a reflux state, carrying out heat preservation and stirring reaction, carrying out reduced pressure concentration after the reaction is finished, recovering the ethyl alcohol, carrying out vacuum drying on the concentrated residues to constant weight, and finally carrying out crushing machine to prepare powder, thus obtaining the pyroglutamic acid-cetyl alcohol esterified.

Compared with the prior art, the invention has the following technical effects:

the process flow of the invention is standardized and systematized, the preparation process of the invention has high welding speed, high efficiency and good quality, the prepared longitudinal submerged arc welded steel pipe has high dimensional accuracy, various performances of the longitudinal submerged arc welded steel pipe are ensured, and the production efficiency is greatly improved while the quality of the longitudinal submerged arc welded steel pipe is improved;

according to the technical scheme, the pre-cleaning treatment is carried out on the welding position of the steel pipe before welding, so that the factors of dust, oil stain, moisture and the like at the welding position, which influence the quality of the welding seam, are effectively eliminated, and further, the pre-heating treatment is carried out on the steel pipe before welding, so that the cleaned welding position is prevented from being polluted again, the quality of the welding seam is prevented from being influenced, the shrinkage stress of the steel pipe is reduced, hydrogen in the welding seam can be promoted to escape, and the generation of air holes and cracks is effectively avoided, so that the ultralow-temperature impact resistance of the welding seam is improved, the prepared longitudinal submerged arc welding steel pipe is high in overall strength and high in mechanization degree, and all performances of the longitudinal submerged arc welding steel pipe are ensured to completely meet the use requirements.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

FIG. 1 is a schematic diagram of a structure of a circumferential weld groove formed when a wall thickness T1 of a single pipe joint is 30-50mm, and a schematic diagram of a structure of a circumferential weld groove and a longitudinal weld groove formed when a wall thickness T1 of a single pipe joint is 50-85 mm;

FIG. 2 is a schematic structural view of a longitudinal seam welding groove formed when the wall thickness T1 of a single pipe joint is 30-50 mm;

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

Example 1

Referring to the attached drawings 1-2, the invention provides a process for preparing a longitudinal submerged arc welded steel pipe for offshore wind power jacket foundation, which comprises the following steps of selecting a steel plate made of DH36 type and having a wall thickness of 60mm, milling two sides of the two edges of the steel plate to reach a preset steel plate width, pre-bending two ends of the steel plate by using a pre-bending machine, reserving a pre-bending straight edge with the wall thickness being 1.5 times of the steel plate in the rolling direction of the steel plate, pre-bending the remaining straight edge by using a press machine or a plate rolling machine on the steel plate, and cutting off the line with the straight edge along after the pre-bending is finished; rolling the pre-bent plate edges by a plurality of rollers to form a single-pipe blank, and performing longitudinal seam welding on the single-pipe blank to obtain a single-pipe joint, wherein the single-pipe joint comprises a straight pipe joint and a conical pipe joint; performing flat-end processing on the pipe end of the single pipe joint; and (4) assembling the single pipe sections subjected to the flat head processing treatment, and performing girth welding to obtain the pipe sections.

In order to ensure the welding quality of a high-quality and high-quantity welding seam, X-shaped grooves with truncated edges of 3mm and both an upward bevel angle and a downward bevel angle of 50 degrees are arranged on a circumferential welding joint and a longitudinal welding joint;

since the weld is cooled at a high speed, a hardened structure is easily generated in the weld and a heat affected zone, thereby causing cracks. Due to rapid cooling and rapid heating, shrinkage stress is generated in the weld and the heat affected zone, thereby causing cracks. In order to prevent the occurrence of a hardened structure in a cold crack, a hot crack and a heat affected zone, the welded joint is pre-cleaned before welding, namely the welded joint is immersed in a treating agent for 20min and then taken out, washed by clear water and dried in the air. The treating agent comprises the following raw material components in parts by weight: 25 parts of pyroglutamic acid cetyl alcohol esterified substance, 5 parts of carboxymethyl-beta-cyclodextrin, 5 parts of PEG-60 hydrogenated castor oil, 2 parts of polyaspartic acid, 2 parts of polydextrose and 300 parts of water; the pyroglutamic acid-cetyl alcohol esterified substance is prepared by carrying out esterification reaction on pyroglutamic acid and cetyl alcohol, wherein the molar ratio of the pyroglutamic acid to the cetyl alcohol is 1:1.1, the specific preparation method comprises the steps of mixing the pyroglutamic acid and the cetyl alcohol, adding absolute ethyl alcohol to dissolve the mixture to prepare a supersaturated solution, adding concentrated sulfuric acid dropwise to adjust the pH value of the solution to acidity, heating the solution to a reflux state, carrying out heat preservation and stirring reaction, carrying out reduced pressure concentration after the reaction is finished, recovering the ethyl alcohol, carrying out vacuum drying on the concentrated residues to constant weight, and finally carrying out crushing machine to prepare powder, thus obtaining the pyroglutamic acid-cetyl alcohol esterified.

And after the pre-cleaning treatment, pre-welding, preheating and post-welding heat preservation treatment are carried out on the steel pipe, the heat affected zone covered within the range of 100mm on the two sides of the welding groove is preheated to 200 ℃ before welding, the steel pipe is heated to 180 ℃ after welding, and heat preservation is carried out for 2 hours. The method effectively eliminates the factors of dust, oil stain, moisture and the like at the welding position which influence the quality of the welding seam by pre-cleaning the welding position of the steel pipe before welding, further prevents the cleaned welding position from being polluted again by pre-heating the steel pipe before welding, reduces the shrinkage stress of the steel pipe, promotes the escape of hydrogen in the welding seam, and effectively avoids the generation of air holes and cracks, thereby improving the ultralow temperature impact resistance of the welding seam, ensuring that the prepared longitudinal submerged arc welding steel pipe has high integral strength and high mechanization degree, and ensuring that all properties of the longitudinal submerged arc welding steel pipe completely meet the use requirements of a wind power single pile project.

The first table shows the welding parameters of the longitudinal submerged arc welded steel pipe for the offshore wind power single-pile foundation:

according to the standard requirements of GB/T2652-:

according to the standard test method standard requirements of the ASTME190-2014 weld plasticity guide bending test, the performance index test results are shown in the table 3:

according to the standard requirements of the Charpy pendulum impact test method of GB/T229-:

comparative example 2

The comparative example is basically the same as the preparation process of the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation in the example 1, except that only preheating treatment is carried out on a welding node before circular seam welding and longitudinal seam welding, and no pre-cleaning treatment is carried out, and the rest is unchanged, so that the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation is prepared.

According to the standard requirements of GB/T2652-:

according to the standard test method standard requirements of the ASTME190-2014 weld plasticity guide bending test, the performance index test results are shown in the table 6:

according to the standard requirements of the Charpy pendulum impact test method of GB/T229-:

comparative example 3

The comparative example is basically the same as the preparation process of the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation in the example 1, except that the longitudinal submerged arc welded steel pipe for the offshore wind power jacket foundation is prepared without pre-cleaning and pre-heating the welding nodes before performing girth welding and longitudinal seam welding, and the other parts are unchanged.

According to the standard requirements of GB/T2652-:

according to the standard test method standard requirements of the ASTME190-2014 weld plasticity guide bending test, the performance index test results are shown in the table 9:

according to the standard requirements of the Charpy pendulum impact test method of GB/T229-:

the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.